Re: LF: Signal_8970Hz

[Roger Lapthorn <rogerlapthorn@gmail.com>]

Will we soon need a Dreamer's Band "band plan", HI? Activity levels/interest is certainly growing now that several stations have shown what can be achieved by radiated propagation, albeit with decent antennas, high power and extremely narrow bandwidth signals.

On the "keep it simple end" of Dreamer's Band work over here, I'm hoping to do some more earth mode experiments on 8.760kHz soon, but the weather here is too bad to get out into the surrounding countryside to look for the signals with snow and ice on the fields and roads. 

My next test is to compare received signals using (a) an earth electrode pair versus (b) the 80cm loop used up to now for receiving. If the propagation is by utilities assisted earth mode conduction then putting a 30m long earth electrode pair across a fenland road should give me very tight coupling to whatever is buried in the roads and lanes; I'm assuming that a loop is formed within the ground to some depth surrounding the entire road and services within it. 

I've still to find out just how far the existing system can reach in all directions, but I know at least 5.3km is achievable with just 4-5W in favourable directions with QRSS3. Clearly this is not radiated propagation. At the weekend I built a small preamp to use with the earth electrode system using a grounded gate FET with the drain circuit tuned to 8-9kHz feeding  into the PC soundcard via an emitter follower. I'm looking forward to some more radiated tests by G3XIZ as I suspect my receiving set-up here using this is now better than before. The simple circuit has good rejection of 50Hz mains and LF/MF broadcast intermod at 9kHz.

Keep up the good work Stefan, Marcus, Ossi etc

73s
Roger G3XBM

2010/11/29 Stefan Schäfer <Stefan.Schaefer@iup.uni-heidelberg.de>

Hi Lubos,

Interesting! And very nice that you are monitoring now! Maybe it was Gerhard/OE3GHB? He is in about 40km to you if i remember correctly. It wasn't me ;-)
Exciting! :-)

73, Stefan

Am 29.11.2010 15:40, schrieb Lubos OK2BVG:

Hello LF!

I saw some signal on 8.97kHz this morning. Was it local QRM only, or any test of transmitting?

Lubos, OK2BVG, JN88KS 

-- 
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
http://www.youtube.com/user/g3xbm
G3XBM   GQRP 1678    ISWL G11088